The present invention relates as indicated to a traffic light lens, and relates more particularly to a lens for a traffic light or signal or automobile taillight in which the light is transmitted through the lens in a predetermined pattern thereby facilitating recognition of the light by oncoming motorists approaching the traffic signal or taillight.
It is a well known fact that many drivers are color-blind and are thus not able to distinguish the "green" and "red" lights on the ordinary traffic signal. This is particularly true during bright sunny days when it is difficult to detect the lights with good vision and where the lenses of traffic lights and automobile taillights have accumulated dust and dirt which impairs the light transmission to a considerable extent through the lens. These conditions are also a hindrance to drivers who are not color-blind but do have some impairment in their vision, not sufficient, however, to prevent their lawful driving of a motor vehicle.
The above indicated problems to color-blind drivers and to drivers having somewhat impaired vision have been recognized in the prior art, and several attempts have been made to facilitate signal light detection by such persons. Attention is directed to U.S. Pat. No. 2,228,835 to W. H. Leppert which discloses a traffic signal in which the red, amber and green lenses are of a particular shape to facilitate detection by the oncoming motorists apart from the color of the light transmitted through the lens. U.S. Pat. No. 2,341,862 to M. Garland likewise discloses a traffic signal in which the ordinary lens has been replaced by a lens which is sectioned for transmitting therethrough light in predetermined and distinct paths thereby to provide a distinctive optical effect upon the eyes of the motorists. Additional patents which provide for arrangements for enhancing recognition of a traffic light include U.S. Pat. No. 3,688,259 to M. Rebillt which discloses an annular light around each lens of the traffic light of a distinguishing color so as to highlight the lens which is sequentially operated, and U.S. Pat. No. 2,190,035 to A. M. Loungway, which provides a series of light bulbs disposed around the signal lens, which bulbs are progressively lighted for the primary purpose of indicating to the oncoming motorists the remaining time in which the light will remain before the light signal is changed.
Although the above discussed prior art does accomplish the general purpose intended, the traffic signals are uniformly characterized by their relatively high cost. The ordinary traffic signals must either be substantially modified to include additional light transmitting equipment or the ordinary equipment must be entirely replaced so that in either event installation costs are increased. Futhermore, such signals are not readily modifiable for use as motor vehicle taillights.